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Learning pack · Foundation · CIE Core

Pythagoras

What's in this pack: printable worksheet PDF, matching answers PDF, and slides (Foundation · CIE Core depth). Pythagoras PPT lesson — Foundation (CIE Core). These slides walk a lower-secondary class through the key ideas with diagrams and worked examples on screen. This page summarises the teaching points for search and revision; download the PowerPoint for the full lesson, and use the companion worksheet and answers PDFs for independent practice.

Resources at the top · full summary · videos with short notes below.

🎒 Resources in this pack

Jump straight to the printable files, or scroll to the summary and videos.

Scaffolded Learning Sheet — attempt the worksheet, then use the Answers for a full written solution.

Lesson slides · narrated video available

Download slides

Files: foundation-21 Pythagoras handout.pdf · foundation-21 Pythagoras handout answers.pdf

Full topic summary

Pythagoras PPT lesson — Foundation (CIE Core). These slides walk a lower-secondary class through the key ideas with diagrams and worked examples on screen. This page summarises the teaching points for search and revision; download the PowerPoint for the full lesson, and use the companion worksheet and answers PDFs for independent practice.

Key learning points

  • Only for right-angled triangles; identify the hypotenuse first (opposite the right angle).
  • To find a shorter side: subtract squares, then square-root.
  • Leave answers in surd form when exact values are required.

Worked example 1 — Find the hypotenuse

Legs 66 and 88. Find the hypotenuse.

Working

c=62+82=10c=\sqrt{6^2+8^2}=10

Multiple of 3-4-5.

Worked example 2 — Find a shorter side

Hypotenuse 1313, leg 55. Other leg?

Working

b=132−52=12b=\sqrt{13^2-5^2}=12

Subtract squares, then square-root.

Worked example 3 — Converse

Sides 77, 2424, 2525. Right-angled?

Working

72+242=252⇒yes7^2+24^2=25^2\Rightarrow\text{yes}

Converse of Pythagoras.

🎬 Topic videos

  • Pythagoras' Theorem (3 of 3: Summary)

    Eddie Woo · 8 min

    Lower Secondary classroom-friendly explainer. Scaffold→stretch friendly; use with mixed-ability groups.

  • Introduction to Pythagoras' Theorem

    Eddie Woo · 15 min

    Lower Secondary classroom-friendly explainer. Scaffold→stretch friendly; use with mixed-ability groups.

  • Proof of Pythagoras' Theorem (Redux)

    Eddie Woo · 15 min

    Lower Secondary classroom-friendly explainer. Scaffold→stretch friendly; use with mixed-ability groups.

  • Pythagoras | CIE IGCSE Foundation Maths (Lower Secondary)

    IMProjectLessons · 8 min

    IMProject original: Pythagoras self-study lesson for Lower Secondary / CIE Foundation. Pairs with Foundation handout + slides. Boards LowerSecondary + CIE; syllabus LS + 0580 Core / 0607 Core.

  • Pythagoras' Theorem (introduction)

    Eddie Woo · 6 min

    Clear classroom intro to Pythagoras. Use when starting right-angled triangles.

  • Visual Proof of Pythagoras' Theorem

    Eddie Woo · 11 min

    Lower Secondary classroom-friendly explainer. Scaffold→stretch friendly; use with mixed-ability groups.

More Lower Secondary packs

Browse the hub Learning Packs & Summary, or open the compact Pythagoras PPT lesson summary.